A framed photograph with messages show support for 9-year-old Jordon “Jordy” Almgren of Discovery Bay during a memorial service at Golden Hills Community Church in Brentwood, Calif., on Friday, May 8, 2015.

Tuesday, with her son seated at the defense table in a room at Contra Costa County Superior Court, wearing a black suit and white shirt, Shultz stepped into the witness stand and plumbed the depths of a mother’s anguish.

“Is that the boy you raised?” asked defense attorney Cynthia Scofield, referring to the confession video.

“No,” Shultz said, clutching a tissue.

William Shultz, 20, is charged with killing Jordon Almgren, his best friend’s little brother, as the boy lay in his bed in the predawn hours of April 26, 2015. He has pleaded not guilty and not guilty by reason of insanity. If he is convicted in the guilt phase — closing arguments could begin as early as Thursday morning — there will be a second trial in which the same jury will determine if he was legally insane or not.

It’s a sad, sad story with anguish that knows no bounds, especially with respect to the Almgren family.

Tuesday was Katherine Shultz’s turn in the eye of the trial. Her first two marriages, producing five kids, ended in divorce. Her oldest child, a student at UC Irvine, died after falling off a campus parking structure.

“That’s so hard,” she said, breathing heavily, when asked about the incident. “There’s a lot of argument that it was a suicide.”

Several members of her extended family, including Katherine herself, have been treated for mental health issues. Nothing could have prepared them for William Shultz’s actions during the spring of 2015.

He began by traveling to Southern California without telling his family. His lack of communication wasn’t the only troubling aspect to his wanderlust. He wrote words on his walls in crayon — “Live Free,” “Money is the root of all evil,” “Don’t kill creativity,” “Relax.” Then he broke the crayons in half and left them on the floor. He left behind a dollar bill meticulously folded into a triangle so all that was visible was the pyramid on the back of the bill.

“It struck me as so odd,” Katherine Shultz said. “I was worried about his state of mind.”

Shortly thereafter, she answered the phone. It was a call from Southern California, her mom telling her, “Billy just showed up at my door.”

William Shultz’s great-aunt gave him a ride back to his family’s home in Discovery Bay. He saw mental health professionals who, Katherine Shultz testified, “did not consider him to be a danger to himself.”

On April 24, Katherine Shultz got a call from her son. He wanted to be picked up from a mall in Tracy.

On April 25, Katherine Shultz said, her son woke up highly agitated, concerned about the end of the world and talking about the Book of Revelation from the Bible.

“I was trying to make him feel better,” she said, “but there was no calming him down.” At one point, William Shultz shoved his mom as she was trying to detain him until police could arrive.

“Then he smiled,” she said, “and told me, ‘You might as well get a gun and shoot me.'”

William Shultz’s great-aunt defused the situation by suggesting he voluntarily allow himself to be taken to Contra Costa County Regional Medical Center for an assessment. A few hours later, he was home, then gone again. Katherine Shultz feared he was going to attempt to walk to South America. Instead, he visited the home of his best friend, Evan Almgren, where he spent the night.

Katherine Shultz and her husband went to a birthday party that night. After they got home, she couldn’t sleep. She finally got up and decided to drive around to see if she could locate her son. It was around 4 a.m., about the time William Shultz was attacking Jordon Almgren.

“This was extremely not in his nature,” Katherine Shultz said crying. “If I could go back to that night … “

Gary Peterson is a sports content creator for the Bay Area News Group. His prior assignments included 31 years as a sports columnist, serving as a general assignment news reporter, covering courts and writing a metro column before finding his way back to sports.

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